Vehicle



Sept. 5, 1944. R. K. JEFFREY VEHICLE 3 Sheets-Sheet l Filed Aug. 16, 1941 ,lrtIll U QOBEQT K. JEFFQEY.

ATTY Sept. 5, 1944. R. K. JEFFREY 2,357,742

VEHICLE i Filed Aug. 16, 1941 3 Sheets-Sheet QoEQT KJEFFQM Aff` " sept. 5, 1944.

R. K. JEFFREY 2,357,742

VEHICLE 3 Sheets-Sheet 3 Filed Aug. 16. 1941 DO BEQT KJEFFQEY.

ATTY.

Patented Sept. 5, 1.944

UNITED f STATES PATENT Iclasica VEHICLE 'Robert K.` Jelfrey,` Columbus, Ohio, assigner to The Jeffrey Manufacturing Company, a corporation of Ohio Application August 16, 1941, Serial No. 407,166

- 6 Claims. l(Cl. ISU-43) This invention relates to a vehicle and particularly to a vehicle adapted to carry coal from a coal loading machine to a conveyor or to an elevatorfor feeding coal into mine cars.

' An object of the invention is to produce an improved device of the above-mentioned type which is adapted to travel in the limited space available in many coal mines.

Another object of the invention is to'provide improved and simplified mechanism for individually drivingv a traction wheel. 1 A further object of the invention is to provvide an extremely compactr and rugged motor-V traction wheel assembly which is adapted particularly for use in a vehicle operable in a coal mine but -which may have other and more general USBS.

Still another object of the invention is to prof vide a mechanism for driving` a traction wheel v which employsa hydraulic engine, which hy-v draulic engine may operate either as a motor or as a pump so that it may drive the traction wheel v or may be driven bythe traction wheel, in which l latter case the pump may be controlled to act as abrake.

Still a further object of the invention is to provide a very compact arrangement of parts in-v cluding a wheel, such as a traction wheel, and a hydraulic motorfor driving it 'through a' com@ pact gear reduction mechanism; thewheel, gear reduction mechanism and driving motor all being suspended so that the wheel may be adjusted to steer the vehicle of which it is a part. Other objects of thel invention willl appear hereinafter, the novel features and combinations being set forth in theappended claims.

In the accompanying drawings,

Fig. 1 is a plan View,- of the vehicle comprising l' my invention; g

Fig. 2 is a side elevational view of the vehicle Fig. 3 is an enlar ed sectional elevational view showing in detail t e preferred construction of one of the combined steering and driving wheels of the vehicle and the associated driving mechanism;

Fig. 4 is a section-al view showing the construction of the head of the hydraulic engine shown electric motor on the -vehicle and anythirrgwhich, e

in- Fig. 3, the view being taken at' right angles'` to that'of Fig.v3; l y

Fig. 5 is a side view of the wheelof Fig. 3 with .its parts removed to show in detail Ithe construc.

Ytion of the speed changing mechanism between tf@ hydraulic engine and the wheel;

l. 6 is a view similar to Fig. 3, showing a modified form of speed changing mechanism between the hydraulic engine andthe. wheel; and

Fig. 'I` is a view similarto Fig. 5, of the modi- "fled form of speed changing mechanism of.

Referring particularly to Figs. 1, 2 and 3 of th drawings, there isA illustrated a vehicle in the form of a coal carrying buggy or shuttle car comprising the preferred embodiment of my invention. It will be .understood that in many of its aspects it is not so limited. I.Said vehicle or shuttle car comprises abody ld which is formed' by opposite sloping side walls Il, Ii forming a receptacle for the material tolbe carried, such as coal, which sloping side walls lead to spaced vertical walls" I2, I2 .(see partitmlarlyFig. 3), between whlch vertical walls l2, I2 there extends a bottom plate .I3 supported by cross-pipes one of which is seen at lijin Fig. 3,01 the drawings,

said cross-pipes I8 being connected at their opposite ends to' anglesills,l one of which is seen at' I5 'inv Fig. 3 of the drawings, said sills I 5 extending longitudinally of the body Ill and' being also connected by transversely extending bars, one of which is seen, at I6 in Fig. 3 of. the drawings, which bars I8 are welded to thel sillsy l5. The bottom plate; I3 forms the bottom of the material receiving receptacle and oi a conveyor which includes endless chains Il, Il` which extend between rear end drive sprockets carried by drive shaft I8 and idler head sprockets at the` front of the vehicle. Transverse flights I9 are interconnected' between the endless chains Il to form the complete conveyor generally designated by the reference character 20. It is evident that r'iriaterialy mayj-be Ldischarged from they car by driving the conveyor 20 -forwarc'lly, and the mechanismfordoing this will now be described.

. Along one side of the vehicle and below one vof the sloping side walls II I provide a large electric motor 2I which is preferably the only is driven is ultimately supplied with energy from said motor 2|. One end of the armature shaft of the motor 2l is connected through a clutch 22 which is operable from an operators station 2l by an appropriate pair of levers preferably interconnected so that the operator may face either forwardly or'rearwardly while riding on the seat 24. l From the clutch 22 avgear, train 25 extendsv through reduction mechanism to the drive shaft I8 of the conveyor 20. 1x1

, The motor 2 lcalso drives a hydraulic pump 26 which supplies hydraulic fluid under vpressure which is employed to driveA lthe'traction wheels of the vehicle, to steer the 'vehicle and also to control the electric cable reel. The specific hydraulic control system is not a part of the inventionrherein claimed and sp it is not illustrated in detail but it is to be understood that any-hy draulic system may be employed consistent with 32 which are preferably all traction Wheels and al1 steering wheels. Each of these wheels is of similar construction and so the description of wheel 29 will be understood to apply to all of them except for certain reversal of parts which is obvious from Fig. 1 of the drawings.

Referring particularly to Figs. l and 2 of the drawings, it will be seen that steering of all of the four wheels 29, 30, 3| and 32 is effected by a single hydraulic piston motor'33 which is connected by a longitudinally and forwardly extending rod 34 and by a longitudinally and rearwardly extending rod |34 interconnected -by a pivot arm 35 to the forwardand rearward pair of wheels which are pivoted about upwardly extendingaxes as hereinafter described in full detail, the for- Ward wheels and rearward wheels each being interconnected by steering mechanism including tie rods 36 land 31, respectively, the opposite ends of each of which are connected to arms rigidly attach to the stub axle oi' the associated wheel; the rms associated with thetie rod 36 being seen at 3 and 39, respectively, and being associated with wheels 30 and 29, respectively. When motor 33 is operated and arm 35 swung about ts center pivot, rods 34 and |34 move in opposite d rection's to swing the front pair of wheels and the rear pair of wheels in opposite directions, as illustrated in Fig. 1 ofthe drawings. As the'construction ofthis steering mechanism is well understood because of its general use in automobile construction, it will not be described in further detail.

Attention is now directed particularly tu Figs. 3, 4 and 5 of the drawings where the' construction of the wheel 29 and the driving mechanism therefor is shown in detail, and the structure herein disclosed forms an important feature of my invention. Said wheel structure 29Vl includes a wheel formed byv a tire, such as a pneumatic tire 40, mounted upon a rim 4| which may include as a part thereof a removable bead ring 4Land a retaining ring 43, though obviously the rim 4| may be of any conventional construction as may the tire 40, and may even embrace a type of wheel adapted to run on a trackfor a wheel adapted to drive an endless crawler such as of the Caterpillar type. The wheel including the rim 4| is mounted l upon a stub axle 44 which includes within its construction a-hydraulic engine 45 which is preferably operable either as a motor to drive the wheel or as a pump to be driven by the wheel. `Said stub axle 44 also includes within its construction atleast part of a speed changing mechanism 461 interpled between the engine 45 and the wheel 29; the rest of the speed changing mechanism, that is the rotating part thereof being rigidly attached to the rim 4|. The entire mechanism comprising the wheell 29, hydraulic engine 45, and speed changing mechanism 46 is mounted as a unit for swinging movement about Aan inclined upwardly extending axis tov provide for steering of the vehicle as previously mentioned, by mechanism now to be described.

Rigidly attached to the frame ofthe vehicle and specically to a spacer 41 which in turn is rigidly attached to the vertical wall l2 and angle sill I5, is a bracket 48 having a top arm 49 and a bottom arm 50. Rigidly but removably attached' to arms 49 and 50 are pivot pins 5| and 52, re-

spectively, the axes of which are in alignment and extend upwardly, though preferably slightly inclined to the vertical. The pivot pins 5| and 52 extend into the-top and bottom cups 53 and 54, respectively, formed in a metal casting 55 comprising the major portion of the stub axle 44 and also forming a housing of the hydraulic engine 45. The innermost end of the pivot pins 5| and 52 support the .stub axle 44 for pivotal movement about their alined axes through tapered roller bearings 56 and 51 within the cups 53 and 54, re-

spectively. Grease seals 58 and 59 seal the cups 53 and 54 withrespect to said pivot pins 5| and 52 to retain greaser therein for the roller .bearings 56 and 51 while also keeping them free of dirt, grit and other yforeign matter. The remote ends of the pivot pins 5| and 52 are provided withappropriate grease iittings leading through central bores of said pivot pins to the interiornof the cups 53 and 54, respectively, so that said/bealigaivv and 51 may be periodically lubricated. l

That portion of the stub axle 44 which forms a housing of the hydraulic engine 45 is provided with a central opening lor recess 50 which is closed by a head 6| shown 'in detail in Fig. 4 of the drawings, and provided with separate hydraulic chambers 62 vand 63 communicating with flexible hydraulic hoses 64 and 65,v respectively. The hydraulic engine 45 is so constructed .that it may operate either as a pump or asa motor and is furthermore reversible either as a pump or as a motor. The flexible hoses 64 and 65 and particularly their inode of connection to the head 6| permit free 4oscillation of the stub axle 44 about the above -mentioned upright axis.

The hydraulic engine 45 includes within the recess a rotor 66 mounted upon and keyed to a shaft 61, ythe axis of which preferably coincides with the axisf rotation of the wheel 29. The rotor 66 is provided with a plurality of axially extending bores or cylinders within each o1' which In some of vthe broader aspects of the invention herein vclaimed the engine 45 may be constructed merely to act asa motor, andrin still even broader aspects the engine. may be an electric motor, but in the preferred embodiment of the invention as herein disclosed, said engine 45 is preferably of the hydraulic type and preferably acts either as a pump or as a motor and is yreversible both as a'pump and as a motor.

Each of the cylinders of the rotor 56 communicates by a port, suchtas port 10, with elongated arcuate ports associated with the chambers 62 and 53 respectively, during rotation of the rotor ,66 so that each of said cylinders is successively connected to a discharge chamber andr a Vpressure y other conditions/,a reverse situation will prevail.

'I'he other end of each of the pistons, such as piston 68, bears against a swash plate 1| lying ina plane at an'angle to the axis of the shaft 61, the swash plate 1| being mounted for free'rotary movement on anti-friction bearings 4with respect to a stationary swash plate supporting casting 12 which is keyed to the casting 55.

It is, of course, obvious that as the rotor 66 rotates, the pistons, such as a piston 68, reciprocate and each makes a complete stroke for each revolution of the rotor 66Jv Hydraulic engines of this general type are well known in the art. For this reason the above description is believed to sulce for a full understanding of the invention herein claimed. It may be stated, however, that for further details of the .precise structure ofthe rotor, swash plate, pistons and associated mechanism of the hydraulic engine, reference is made of my co-pending application, Serial No. 348,765,

illed July 31, 1940, now Patent No. 2,331,694, dated October 12, 1943, for an Improvement in hydraulic pump or motor, though of course other equivalent known engines maybe employed.

The casting 55not only forms a-housingof the engine 45' but also forms a part of the speed changing mechanism l46* and Aat its left-hand end', as viewed in Fig. 3 'of the drawings, it has rigidly attached to it a plunger holding guide ring 13 which is clamped rigidly to said casting 55 Vby a stub axle extension member 14, said member 14, `ring 13 and casting 55 being rigidly connected by machine screws 15 which extend loosely through member 14 and ring 13 and are threaded into said casting 55.

Ri idly but removably attached to the rim 4| and within the radial confines thereof I provide a housing 16 forming a part of the speed changing mechanism 46 and also forming a hub for the wheel 29, said housing 1li-being formed-by members 11l and'18 which are removably attached together by machine screws V'I9 and by a removable cap 80 removably attached to the member 11 by machine screws 8|. lSaid housing 16 is removably attached to the rim 4|' by meansof machine screws 82which extend through an integral flange on the rim 4| and are threaded into the member 11. The housing or hub 16 is journa-led on the stub axle 44 by spaced roller bearings v83, 84, the former'being interposed between the extension member 14 and the housing member'11', and the 'it possible to construct such a speed reducer with the. desiredv high ratio of speed reduction between the wheel 29 and the engine 45 whllerequiring the minimum of space, thus making it possible 'to obtain a. relatively high speed ratio in a compact speed changingunit which may be entirely incorporated within the radial confines of the wheel' 29. It. is, of course, to be understood that the compact structure provided by the stub axle 44 including thecasting 55, also makes for this compactness of the driving unit which I have also found may be used with other types of Speed changing mechanism as hereinafter described in connection with Figs. 6`and '1 'of the drawings, but as above stated, I prefer the structure illustrated in` Figs. 3, 4 and 5, for here the speed changing mechanism mayhave a gear ratio which is almost unlimited, and in practice may be anywhere from to 1, to 100 to l.

Intermediate its ends the rotor shaft 61 of the engine 4 5 is mounted in a ball bearing 81 carried in an appropriate recess in the casting 55 of stub f hereinafter described more completely.

Mounted on the eccentrics 98 and 9| are ball bearings 92 and 93, respectively. The eccentric 96 and co-operating ball bearing 92 operate a series of radial plungers which extend radially through radial slots in the plunger holding guide ring 13,'as clearly illustrated in Figs. .3 and 5 ofA the drawings. The plungers 94 are provided with of each plunger as permitted by the eccentric 90.

In other words, as the plungers 94 on one side are moved outwardly by eccentric 98, plungers diametrically opposite are retracted and intermediate plungers assume an intermediate position be- A latter being interposed between the casting moving the screws 8|, the cap 89 may be removed' whereupon access is had toj the retaining ring 85. This ring 85 may be removed by removing screws SaidI housing' 16 86 thus permitting removal of the wheel 29 and i the housing y.16 from the stub axle 44, This, of

l course, is'not a normal operation and is described merely to indicate the possible disassembly of the unit. To replace a tirethe lscrews 82 are removed, whereupon the rim 4| and tire 40 are readily removable.

Attention is now directed yto the/,mechanism -which in addition to that previously described goes to make up the speed changing mechanism 46. It may .be stated that the lspeedchaiiging 5 echanism disclosed is of vthe type generally known in the art as a heliocentric reducer. of the double eccentric'type and AI prefer this type of speed reducer to all others because I have found tween thevfully extended and fully retracted posiy tioriin a manner obvious from an inspection of Fig. 5 of the drawings.

(Zo-operating with the tapered outer ends of th plungers 94 is a ring gear or circular rack 96 which is removably attached to the housing 16 and preferably to the member 18 thereof and held gisairst rotation relatively thereto by key 91 (see s. keyed to the housing or'hub 16.

Associated with the eccentric 9| and ball bearing 93 ,is a series of plungers 98 similar to the plungers 94 whichv are provided with a plunger retracting ring 99 and co-operate with theI ring gear or circular rack |00 als6 removably attached ytothe member 18 while being keyed thereto against rotation by the key 91.

It is evident that for each rotation of the shaft 61, Aany given plunger 94 will make on.complete oscillation, and the-plungers 94 are so relatedto between the rotation of the shaft 51Aa`-nd otation" of the rack96 andthose parts attached to it, and

Y the arcuate angle of irotation of the rack 96 for each reciprocation of a given plunger mine this reduction ratio. l

Inother words, the circular rack 96 is will deterl The contact between the outer end of each plunger 94 and the rack 96 is a combination of sliding and rolling action. and each plunger is t working from the time it enters the rack tooth until it reaches the root ofthe tooth. Furthermore, generally over one-third of the plungers are always working at the same time in `different progressive stages, thus insuring even distribution of the load n said plungers. Furthermore, the plungers 94 and 96 are working simultaneously and in diametrically opposite pairs so that the forces transmitted to the housing 16 are equalized at all times. The operation of the plungers 98 and associated ring |00 is, of course. the same as that of plungers 94 and associated ring 96, except that the two are 180'out of phase, as above described.

In the operation of the device, when the engine 45 is operating as a motor, hydraulic fluid under pressure will be supplied to one of the chambers 62 or 63 while the other acts as an exhaust chamber to cause rotation of the rotory 66 in one direction when the chamber 62` is a pressure chamber and in the opposite direction when chamber 63 is a pressure chamber, Rotation of the shaft 61 in 25 one direction will operate vthrough the aforedescribed cams 90 and 9|, plungers 94 and 98 and rings and |00 to rotate the housing 16 in one direction at a greatly reduced speed compared to the speed of rotation of shaft/61. Rotation of shaft 61 inthe opposite direction will cause reverse rotation of the housing 16. Since the housing 16 is, of course, attachedlto'therim 4| of lwheel 29, they will follow its movement and direction of rotation. Under such operating conditions the engine 45 will, of course, be operating as a motor.` Conversely, rotation f the wheel 29' will cause much higher speed rotation of the. shaft 61 andY rotor 66 of thel engine 45 and may drive it, under which conditions it will act as a pump, and by throttling the output thereof said pump may be employed as' a brake, As previously stated, reverse rotation of the wheel 29 will produce reverse rotation of the shaft 61 when the engine 45 is being driven as a pump. 45.

It should b'e particularly pointed out that th -compactness oi' the complete unit including the engine 45 and speed changing' mechanism 46 whereby they all consume a minimum of space andyet provide 'a very strong and rugged conf struction, Ais the result of a number of factors. 011e of the important contributions to this compactness, consistent with the very rugged construction, is the fact that the hub 44 forms in part a housing of the engine 45 and in part .amon- 55 rotary support for the wheel 29,.. Another'factor which is particularly important where the redic- .tion ratiol 'is high, for;.-example, 20 to 1, is the heliocentric type of speed-reduction mechanism employed. VA further factor is the provision of a hydraulictype of motor-because this type of motor will produce alarge` torque for -sizeor physical dimension-than most other mctors, sucl1 as an electric motor. and-while, as above stated, in' certain broad aspects ofthe lnventionan relectric".

v46,`in the preferred embodiment' of e invention .f and'in'amore specific aspect thereo ehydrulic type of motor or-cngine is definitelyto be preferred because of this 'smaller physical-size for the same torque, as compored withrth'e 'rated torque ofan electric, motor. Still/another im.-

rtantiactor is thel particular type of hydraulic engine employed. That isthe hydraulic engine bot the axially reciprocating piston type -75 the overall dimensions of this type of hydraulic engine and particularly the circumference thereof are lower than many other types of hydraulic engines, suchvr as the radial piston type. for example. Furthermore, another advantage of a hydraulic engine over an` electric motor is that there is less temperature rise for a hydraulic motor due to the cooling effect of the hydraulic system on the hydraulic uid as it flows torand from said hydraulic engine.

From the above description particularly of the speed changing mechanism 46 and the speed ratios 'available with the particular heliocentric type f mechanism discmsed, it is evident that this arrangementis particularly adaptable where. high torques are required', and the engine, speed changing mechanism and wheel construction of Figs- 3, 4 'and 5 is particularly useful to'vehicles of heavy construction or those required to carry heavy loads, requiring said relatively high torques.

Where the vehicle is of lighterconstuction or Y the total weight of material to be moved is lighter, a more simple type of speed changing mechanism may be employed, and attention is now. directed particularly to Figs. 6 and '7 oi the. drawyings wherein I have shown a modified form oi speedv changing mchanisni |46 which may be employed where the speed changing ratio is'lower than that above suggested, though the speed y denitely pointed out, the structure disclosed in f Figs. 6 and 7 will be the same as that of Figs.

3, 4 and'5'.' Referring particularly to said Figs. 6 and 'If'I provide astub axle |44 comprising a casting |55having an opening or recess |60 withvided with a pinion |0| which meshes with a larger gear |02 mounted on a pivot pin |03 which is held Iin the right-hand portion of the castingv |55 which forms the non-rotary or axle part of said stubaxle 44. A retaining key |04 is provided to maintain the pin |06 in place.

' Formed integral 'with the gear |02 is a smaller gear |05 which meshes with an interior ring gear' |06 which has a' ange rigidly attached to and forming. a part ofthe housing |16 of the speed changing mechanism |46; said housing |16 being r formed by membery and |06 which are bolted to opposite sides of. the frangel of said ring gear |06by cans of machine screws |06, 'Ihe'hous- Aing |16J also includes a removable cap |60 removably attached by'machine screws |6I. fAlso removably attachedto the housing |16 by meansof lugs and bolts la: is the'rim Meurthe .wheerj tion to the rim 4| previously described. motor may besubstituted 4for the motor o'r -engine -f From the description sol far given it' is, v'of course, evident that in describing the construetion 4shown "in Figs.'6 and '1, reference'characters are used the same as those used to describe Isimilar' elements of the 'mechanismofFi88. 3, 4 andv .5, :except-that the number hasjbeen increed by one hundred.

To secure thecwheel l|26 for rotary movenent non the ,hub |44 I provide spaced roller bearings |60 and |(04and a removable ringl. A grease a brake.

ble function of the engine |45 aswell as the' seal III) isy interposed between the inner flange of the housing |16 and the adjacent portion of the non-rotary stub shai'tI |44. It should also be pointed out that the device of Figs. 3, 4 and 5 contains a similar grease seal seen at Hi. These grease seals may be of any standard construction and I- have illustrated different forms in the two devices. lI'he function of both is the same and is, of course, to keep grease 'on the wheel bearings 83 and 84 or |83 and |84 and also to prevent dirt, lgrit or other foreign matter from reaching Said bearings. I

The structure by which-the casting |55 is supported for swinging movement about anlupwardly extending inclined axis is the same in Figs. 6 and 'I as the structure of Figs. 3, 4 and 5 and therefore will not be described again.

In the structurgdisclosed in Figs. 6 and 7, when the engine |45 is operating as a motor, the sh aft |61 will be driven and will drive the wheel I 28 throughthe speed changing mechanism |46, the gear train beingl from shaft itl through pinion i gear |02, integral gear E05 and ring gear |06 meshing therewith which is rigidly attached to and forms a part of the housing or hub which in turn is rigidly attached to the wheel |29 through the rim HH. This speed changing mechanism, of course, is reversible and so in case the wheel |29 is acting as a driver, the shaft |61 will be driven and the engine |48 will operate as a pump, and like the engine its hydraulic fluid output can be throttled. whereupon it will act as It is, of course, evident that the douengine 45 to act 'either as a brake or as a driving mechanism contributes appreciably`y to the l simplicity of thel mec anism because it elimiand 5, all of the advantageous characteristics of the structure of Figs. 3, 4 and 5 are presented in the structure of Fig 6 and 7. It is, of course, evident that the spee changing mechanism of Figs. 6 and 7 is less complicated, less expensive Obviously those skilled'in the art may make various changes in the details and arrangement 'ing motorprovided -with axially extending pistons in a rotor within said axle, said axle forming at least part of the housing and stator of said motor, andr gearing driven byv said rotor and driving said wheel.

2. In a vehicle,the combination with a casting providing a stub axle, of a traction wheel. means including a bearing mounting said wheel on said axle for rotation, a hydraulic engine having axially extending pistons in a.A rotor within said axle, said axle thereby forming at least in part a housing of said engine, and. speed changing gearing interconnecting the rotor and said wheel.

and requires'less space thano that ofthe mechapose, this structure is to be preferred and this will apply to a great many, if not most, vehicles and particularly to those shuttle cars and similar equipment. f

In the operation of the vehicle it is evident 3. Driving mechanism for -a vehicle comprisingy a wheel, a hydraulic driving motor and a speed changer connected between said motor and wheel, said speed changer including a rotating' member attached to said wheel and comprisving a housing of, said speed changer, a non-rotating member having a portion extending kinto said housing, spaced bearing means interposed between said non-rotating member and said rotating member to provide for rotation of the latter while being supported by the former, said non-rotating member also having a portion forming the stator of said driving motor, said driving motor also including a rotor having axially extending pstons and mounted on a vshaft extending along the axis of rotation of said wheel, and said speed changer also including gear means connecting the motor shaft with said rotating member.

4. Driving mechanism for a vehicle comprising a wheel, a driving motor and a speed changer .connected between sai'd motor and wheel, said speed changer including a rotating member at.-

tached to said wheel and comprising a housing of said speed changer, a non-rotating member having a portion extending into said housing, spaced bearing means interposed between said non-rothat'in the preferred embodiment of my inven-y tion all four wheels are traction wheels as well as steering wheels, though it is,of course' evident that as to certain aspects of my invention #traction may be limited to eitherN the front wheels or the rear wheels, and steering may likewise be limited to,either the front wheels or the'rear wheels, and the traction may be on the same pair of wheels or traction may be applied to-one,

pair of wheels and steering to the other. I pretraction wheel and' also makes possible the turning of the machine in a minimum of space.

vtating member and said rotating member to provide for rotation of the latter while being supported by the -former, said `non-rotating member also having a portion forming the stator of said driving motor, said driving ,motor also includparallel with theaxis of rotation of said wheel.

,5. A-motorized wheel including a single casting providing a hydraulic motor housing and also at least in part a' reduction gearing housing, a hydrauli motor rotor mounted for rotation in said ing, rthe outer of said bearings ybeingsmaller than the inner one whereby the outer bearing is moun'ted on a reduced portion of said casting as ompared with the portion on which the inner bearing is mounted, a nna'i drive gear on the interior of said wheel positioned between said bearings,

additional reduction gears providing `a driving connection betweensaid rotor and said wheel gear and at least in part being housed within said casting. and means formed as an integral partl `assainir roller bearings on said casting, the outer of said 'bearings being smaller than the inner one where- .by the outer bearing is mounted on a reduced portion oi said casting as compared with the portion on which the inner bearing is mounted, a nal drive gear on the interior of said wheel positioned between said bearings, additional reduction gears of said casting tor mounting the entire motorized wheel for steering as a unit, whereby the load on said wheel is transmitted `from thev bearings -through an. integral casting to saidv mounting' means. .n

6. A motorized wheel including a single castin providing a motor housing and 7also at least in part areduction gearing housingI a motor A rotor mounted for rotation in said housing formed by said castinma wheel mounted on laterally spaced providing a driving connection between said rotor and said wheel gear and at least in part being housed within said casting, and means formed as an integral part of said casting'for mounting -15 said mounting means.

the entire motorized wheel for steering as a unit, whereby the 4load on said wheel is transmitted from the bearings through an integral casting to ROBERT K. JEFFREY. 

